docs: review grammar in tests/london, tests/homestead, tests/paris (#50)

Reviewed 17 files across tests/london/**/*.py, tests/homestead/**/*.py,
and tests/paris/**/*.py for grammar issues. No corrections needed -
all docstrings, comments, and string messages are grammatically correct.

Co-authored-by: Claude <noreply@anthropic.com>

Author: danceratopz

repo_subpaths_for_grammar_check.md

@@ -18,5 +18,5 @@ Status legend: `[ ]` pending, `[~]` in progress, `[x]` complete
 - [x] `tests/byzantium/**/*.py` (~11 files)
 - [x] `tests/istanbul/**/*.py`, `berlin/**/*.py` (~18 files)
 - [x] `tests/constantinople/**/*.py`, `amsterdam/**/*.py` (~16 files)
-- [ ] `tests/london/**/*.py`, `homestead/**/*.py`, `paris/**/*.py` (~17 files)
+- [x] `tests/london/**/*.py`, `homestead/**/*.py`, `paris/**/*.py` (~17 files)
 - [ ] `tests/*.py`, `tests/common/**/*.py`, `tests/evm_tools/**/*.py` (~5 files)